Simplify our container usage

[marcpopMSFT]

Based on offline guidance, simplify our container usage in main to use the azure linux images for all linux builds. ASP.NET followed this guidance and there change was here:
https://github.com/dotnet/aspnetcore/pull/60260/files

Open questions:

1. I kept some of the sdk job legs that had different parameters passing in for osProperties but we should review and determine if they really are different
2. The VMR now handles the production of the packages so we probably don't need most of these in the CI build either. I just changed the container they built on but perhaps we can remove some/most of those as well as they are just for validation in the SDK repo at this point.

[Copilot]

Pull Request Overview

This PR simplifies our container usage by replacing various Linux container images with a unified azureLinux30Net10BuildAmd64 image for all Linux builds. Key changes include:

• Updating container definitions in sdk-job-matrix.yml to use azureLinux30Net10BuildAmd64.
• Removing several container entries in .vsts-pr.yml and .vsts-ci.yml and replacing them with azureLinux30Net10BuildAmd64.
• Adjusting helixTargetContainer and other properties to conform with the new container usage.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
eng/pipelines/templates/jobs/sdk-job-matrix.yml	Updated container and helixTargetContainer for ContainerBased jobs to the new azureLinux30Net10BuildAmd64 image.
.vsts-pr.yml	Removed redundant container definitions and added azureLinux30Net10BuildAmd64 for PR validation.
.vsts-ci.yml	Unified container references across different build categories to use azureLinux30Net10BuildAmd64.

Comments suppressed due to low confidence (2)

.vsts-ci.yml:194

• Ensure that azureLinux30Net10BuildAmd64 can support RPM-based distributions as indicated by the '/p:IsRPMBasedDistro=true' flag, since the original container was centos-based.

container: azureLinux30Net10BuildAmd64

.vsts-ci.yml:211

• Verify that using azureLinux30Net10BuildAmd64 in the Musl category is compatible with the musl runtime requirements, as the previous configuration used an alpine-based container.

container: azureLinux30Net10BuildAmd64

[richlander]

Can you change the name "Portable"? I don't think it is meaningful. Perhaps "glibc" is what is intended.

[marcpopMSFT]

@richlander do you mean everywhere that the string "portable" is used? It's used in property names and category names. I honestly can't recall the history around that naming.

[richlander]

Right. I am suggesting to change it to something currently meaningful. Our build definitions should be clear. If we don't know what a term means, we should change it.

musl is there (which has a clear meaning). The most obvious change is to find a contrasting term, which is glibc.